1. Technical Field
The present invention relates to telephone calls placed over the Internet, and more particularly to a method that uses a tree search for selecting a gateway server to terminate the Internet telephone call.
2. Background Information
One of the most exciting recent developments in the Internet is the transmission of voice data packets over the Internet. This development allows the Internet to be used for completing long distance telephone calls. For example, U.S. Pat. Nos. 5,867,495 and 5,867,494 illustrate a system that allows telephone calls, data and other multimedia information to be routed through a hybrid network that includes transfer of the information across the Internet.
In a typical Internet telephone call, a call initiating gateway terminal receives a normal voice telephone call from a PSTN system and converts it to a digital voice data packet format that can be transmitted over the Internet. The International Telecommunications Union (ITU) standard H.323 sets a protocol to be used in such processes. On the receiving end, a call terminating gateway terminal receives the call from the Internet and converts the call back to a format that can be transmitted over the PSTN system. The call is then routed over the PSTN system to the receiving party.
In order to make this technology practical to use, a methodology is needed for selecting call terminating gateway terminals.